Organic semiconductor materials are used in organic photoelectric conversion devices such as, for example, organic solar batteries, optical sensors and the like. When, among organic semiconductor materials, especially a polymer compound is used, a thin film can be fabricated by an inexpensive coating method and production cost of a device can be reduced.
For improving various properties of an organic photoelectric conversion device, a variety of polymer compounds are deliberated for an organic semiconductor material constituting the device. For example, there is a suggestion on a polymer compound obtained by polymerizing 9,9-dioctylfluorene-2,7-diboronate and 5,5″″-dibromo-3″,4″-dihexyl-α-pentathiophene (WO 2005/092947).
However, the above-described polymer compound has a problem of insufficient absorption of light having long wavelength.